Note: This discussion is about an older version of the COMSOL Multiphysics® software. The information provided may be out of date.

Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.

How to express the difference in temperature between two elements? (Lumped radiation)

Please login with a confirmed email address before reporting spam


Hello dear colleagues,

I am modeling heat transfer in a porous packed bed and I want to avoid T^4 terms (numerical stability), so, I want to model radiation in a simple way. The idea is to either lump radiation into conduction or make a simple source term for it.

The latter option would yield something like:
Radiation heat transferred = Boltzmann_constant * emissivity * surface_between_elements * average_temperature * (temperature_element_1-temperature_element_2)

OR: Q_rad = sigma * epsilon * T_av^3 * (T_1 - T_0)

But for this I need the temperature of the neighboring elements. How do I call those? Is there a better way to describe this idea? Is there a way to properly describe this using dT/dx (like conduction) ?

Thanks for any suggestions. Kind regards,

Ray

1 Reply Last Post 26.06.2012, 04:04 GMT-4

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 26.06.2012, 04:04 GMT-4
Has no one else ever had to do something like this in COMSOL?
Please, if you know anything, let me know.

Thanks you and kind regards,

Ray
Has no one else ever had to do something like this in COMSOL? Please, if you know anything, let me know. Thanks you and kind regards, Ray

Note that while COMSOL employees may participate in the discussion forum, COMSOL® software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team.